1. Field Of The Invention
The present invention relates to a fastening means including a screw having a recess for receipt of a tool, and including a sleeve having an outer thread and having means for receipt of a further tool, which sleeve is rotatably supported on the screw and guided thereupon against an axial movement relative thereto, such that the screw and/or the bolt may be rotated.
2. Description Of The Prior Art
Fastening means of the kind set forth above are generally known. According to a known design the sleeve is pushed onto the screw from the side having the thread and is held on the screw by means of a collar which has been rolled in or by means of arresting members. This design features, however, the drawback that the cross section of the screw is weakened considerably, which leads often to a rupturing of the screw.
According to a further known design the sleeve is slotted along a certain length thereof, such to hold the sleeve at the head of the screw or at a projection at the screw, whereby the sleeve is pressed over the head of the screw or over the projection. The drawback of this design is that the sleeve must consist of an elastically deformable material in order to allow a placing thereof onto the screw, and that due to an accordingly selected material it is possible that the portion of the sleeve which is engaged by a tool can deform when using the screw. A hardening of screws including the sleeve placed thereupon leads to a jamming of the mounted sleeve.
A further drawback of both designs is that their production is quite expensive.